The main aim of this descriptive cross-sectional study is to assess the prevalence of chemsex substance use disorder among chemsexers via an online self-questionnaire.

Chemsex appeared in Europe around 2006 and in France in 2010. It involves the use of psychoactive substances in a sexual context to enhance, initiate, facilitate or prolong sexual intercourse through the psychoactive effects of the molecules consumed. These molecules are essentially synthetic cathinones, GHB/GBL, MDMA, methamphetamines, cocaine and ketamine. These products are often used in combination with erectile dysfunction treatments (side effects of the molecules). This practice is thought to affect almost 20% of MSM.

This use has numerous social, somatic, psychiatric and addictive consequences. Studies have mainly focused on infectious risks, psychiatric complications (e.g. anxiety and depression) or the prevalence of this phenomenon. However, no study has assessed the prevalence of chemsex-related substance use disorders among these users.

Inclusion Criteria:

• Be 18 years of age or older.
• Proficiency in written French
• Have practised chemsex at least once in the last 12 months.
• Agree to participate in the study.

Exclusion Criteria:

• Have not experimented with chemsex in the last 12 months
• Participation in other ongoing research
• Insufficient written comprehension of French